External device to controll power to 1 device?

[Leftover]

Just curious if anyone has a tutorial or has ever worked up a home built device they connected to the parallel port or something and used it to controll maybe a lamp or something? Personal project here, not school related, I just think it would be cool to be able to do stuff like that.

[Andy]

umm some one made a tic tac toe using a breadboard, some logic gates and leds controled by the parallel port a while back

[Leftover]

I know the basics of interfacing projects, I just curious to know what it takes to switch power on and off like that and what type of code it would be.

[Tony]

you basically wire your setup to computer's parallet port (assuming you have one) and write a program to send (or read) current over a set of pins.

parallelput() has an ability to actives up to 8 pins
and
parallelget() could check for feedback sygnals over 5 other pins.

So in theory you can have up to 8 motors that you can turn on/off based on up to 5 mechanical inputs such as buttons and switches..

Realistically though, you might want to be able to control the direction of the motors as well, so that takes out of the number of outputs available. Furthermore parallet port provides just 2.4 V of power per pin, so you can expect to work with small motors only.

[Random]

I did something like this with a friend. We used C to control different pins on the parallel port and we made a conector using an old parallel port cable. That went to a couple relays which controlled stuff with a larger power supply powering it. The problem was that the signal from the parallel port was getting so weak that the cable we had to use was very, very short.

We also made a thing where we hooked up 4 LEDs to the cable and made a little lightshow using C. Anyways, relays, they are key.

[wtd]

tony wrote:

you basically wire your setup to computer's parallet port (assuming you have one) and write a program to send (or read) current over a set of pins.

parallelput() has an ability to actives up to 8 pins
and
parallelget() could check for feedback sygnals over 5 other pins.

So in theory you can have up to 8 motors that you can turn on/off based on up to 5 mechanical inputs such as buttons and switches..

Realistically though, you might want to be able to control the direction of the motors as well, so that takes out of the number of outputs available. Furthermore parallet port provides just 2.4 V of power per pin, so you can expect to work with small motors only.

Or you could just have different combinations of inputs for different actions.